Black malleable iron. Larger size listing is for Male thread, small size listing is for Female thread. Each fitting is individually flag tagged. Import. Mueller logo cast into body of each fitting. 100% inspected and quality tested. All fittings meet the following specifications: Material: ANSI/ASTM A-197 Dimensions: ANSI/ASME B.15.3, B16.14, B16.39. Threads: ANSI B1.20.1.